Life Extension Magazine®
Mature man sitting in front of chess board taking natural supplements for cognitive function

Boost Brain Processing Speed, Learning, and Retention

“Smart drugs” quickly boost cognition. For those seeking a natural approach, four plant extracts improve brain processing speed, memory, learning, and concentration.

Scientifically reviewed by: Dr. Gary Gonzalez, MD, on October 2021. Written By Deep Shukla, PHD.

Nootropics are often called “smart drugs.”

They enhance brain processing speed, learning, and alertness.

Many nootropics used today are off-label drugs that can have unwanted stimulating effects.

Those preferring a more tranquil approach may consider plant-based nootropics that have demonstrated cognitive-enhancing properties.

These clinically studied plant extracts have been shown to boost memory, enhance brain processing speed, and improve concentration and alertness.

What Are Nootropics?

Brain generated image being supported by plant-based nootropics

Nootropics are different from compounds that protect against brain aging or cognitive decline.

They quickly boost cognitive performance, brain processing speed, mental alertness, and attention in healthy adults.

They may achieve this by increasing blood flow to the brain, combating inflammation, modulating levels of neurotransmitters, and increasing the number or effectiveness of synapses (that enable neurons to communicate).1-3

Scientists have identified plant-based compounds shown in human studies to improve cognitive function, processing speed, and memory.

Bacopa Monnieri Improves Cognition

Bacopa monnieri flower and leaves traditionally used for pain

Bacopa monnieri, is an herb traditionally used in Ayurvedic medicine to treat inflammation, pain, asthma, and dementia.4

Ancient texts dating back to the sixth century indicate that Bacopa monnieri was used to enhance memory and sharpen the intellect.3

Clinical studies suggest that Bacopa monnieri can improve cognitive performance in healthy young and elderly individuals.5-13

These studies indicate that Bacopa monnieri extracts may enhance:

  • Acquisition of new memories
  • Ability to retain and recall memories
  • Ability to sustain attention and speed of attention
  • Rate of learning
  • Working memory
  • Speed of information processing

One human study found that daily intake of Bacopa monnieri extract for 12 weeks led to an improvement in working memory (the ability to store and use short-term information).8

Measurements of brain activity showed that those taking Bacopa had a more rapid onset of activity patterns associated with attention and information processing.8

Bacopa monnieri use also resulted in a decline in activity of the enzyme acetylcholinesterase.8 This enzyme breaks down the neurotransmitter acetylcholine, which is involved in memory and attention.14

Laboratory experiments suggest that Bacopa monnieri may also improve cognitive function by:

  • Generating new nerve cells in the hippocampus,15 a brain region that plays a critical role in learning and memory,16
  • Enhancing the branching and length of dendrites (nerve cell extensions that receive signals from other nerve cells)1,17,18
  • Improving cerebral blood flow,19
  • Inhibiting the release of inflammatory cytokines and blocking enzymes involved in inflammation,2,20
  • Modulating neurotransmitter production,21 and
  • Improving the activity and levels of enzymes and nerve growth factors that are involved in maintaining and creating new synapses.3,15,22,23

Gotu Kola Boosts Brain Function

Gotu Kola leaves that through studies enhance cognitive functions

Gotu kola (Centella asiatica) is a flowering plant native to Asia.24,25 It has long been used in Ayurvedic medicine to boost memory and cognition.26

Clinical studies suggest that gotu kola can enhance cognitive functioning in healthy adults.26,27

One study of adults ages 35 to 50 showed that intake of gotu kola daily for two months improved cognitive performance, including the retrieval of memories and speed of information processing.27

In another study, daily intake of gotu kola extract for two months improved the reaction time and accuracy of working memory in healthy older adults.26 Researchers also found an increase in brain activity associated with attention during a cognitive task.26

Animal studies confirm that gotu kola can increase the number of synapses, reduce oxidative stress, and improve the function of energy-producing mitochondria in the hippocampus.28,29

Treatment with gotu kola extract also stimulated the growth and maturation of nerve cells and the formation of synapses in lab cultures of nerve cells from the rat hippocampus.30

Like Bacopa, gotu kola enhances the elongation and branching of dendrites in the hippocampus and the amygdala in adult rats.31,32 These changes are associated with improvements in learning and memory.

What you need to know

Physician pointing to brain scans of those taking nootropics like gotu kola

Enhance Cognitive Function

  • Nootropics are compounds that can enhance cognitive performance in healthy adults.
  • Clinical trials show that extracts of the plants Bacopa monnieri and gotu kola and the carotenoids lutein and zeaxanthin can safely improve memory, learning, concentration, and information processing speed.
  • These compounds reduce oxidative damage and inflammation in the brain and improve communication between brain cells.

Carotenoids and the Brain-Eye Connection

Infographic of brain-eye connection

Carotenoids are a group of pigments found in many fruits and vegetables.

Lutein and zeaxanthin are closely related carotenoids that play a vital role in maintaining healthy vision. They help protect the macular density necessary for visual function.33-38

A majority of the lutein and zeaxanthin obtained from the diet is taken up by the retina, the innermost layer of the eye, and concentrated in a region near the center of the retina known as the macula.

The retina is composed of nerve cells and is an extension of the brain. Researchers have discovered that lutein and zeaxanthin also accumulate in the brain and play an important role in cognitive function.39,40

Scientists are able to easily measure levels of lutein and zeaxanthin in the macula and have found that they correlate with levels in the brain. 41,42

They have also determined that levels of lutein and zeaxanthin in the macula and blood serum are associated with cognitive function.43-46 For instance, individuals with mild cognitive impairment or Alzheimer’s disease have lower levels of these carotenoid pigments in the macula or blood serum.43,47

Lutein and Zeaxanthin Enhance Mental Performance

Numerous clinical trials have explored the effects of lutein and zeaxanthin intake on cognitive performance in healthy young and older adults.48-51

These human studies show that lutein and zeaxanthin intake can improve:

  • Speed of information processing,48,49
  • Reasoning ability,50
  • Memory,50,52
  • Visual motor reaction,49
  • Attention,45,51
  • Verbal and visual performance,50,53 and
  • Cognitive flexibility, the ability to shift mental strategies according to the task.51

A review of previous studies published in 2020 found that lutein and zeaxanthin were consistently effective in improving attention and long-term recollection of events, situations, and experiences.54

Using brain scanning, scientists have found that lutein and zeaxanthin levels in the serum and macula are associated with increased integrity of white matter (which consists of nerve fibers that connect brain cells) in older individuals.55

Carotenoids can also enhance the expression of proteins that form gap junctions.39 Gap junctions are channels that allow neighboring cells to directly communicate with each other. Increasing gap junction communication may enhance cognitive performance.40

Lutein and zeaxanthin appear to increase cooperation between brain regions that previously functioned in isolation,56 to increase blood flow to the brain,53 and to combat oxidative damage in the brain.57,58

All of these actions can help improve cognitive performance.

Combining these carotenoids with Bacopa monnieri and gotu kola may help maximize the brain’s full potential.


Doctor and man discussing adding plant-based nootropics to routine

Nootropics can enhance cognitive performance in healthy individuals.

Animal and human studies show that the carotenoids lutein and zeaxanthin and extracts of the herbs Bacopa monnieri and gotu kola enhance various aspects of cognition in healthy young and old adults.

These natural nootropics have anti-inflammatory properties that protect nerve cells.

Natural nootropics can also modulate the connections between nerve cells to enhance learning and memory.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.


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